Semi-trucks (“trucks”) refer to a type of freight vehicle, having a front vehicle (sometimes referred to a “tractor” or “tractor truck”) that can attach and transport a trailer (a “semi-trailer,” “freight trailer,” or “cargo trailer”). Semi-trucks, in general, pose numerous challenges with respect to their drivability given the size, geometry, and weight. For this reason, truck drivers are often required to earn separate credentials in order to operate a semi-truck.
The Mansfield bar of a cargo trailer—also known as an Interstate Commerce Commission (ICC) bar, underride guard, or rear impact guard—is a safety bumper that prevents vehicles from under-riding the cargo trailer from the rear, which can result in passenger compartment intrusion and gruesome injuries and fatalities. The Mansfield bar's namesake is the deceased actress, Jayne Mansfield, who was killed in a vehicle collision with an unprotected rear of a cargo trailer, causing the National Highway Traffic Safety Administration (NHTSA) to mandate the installation of Mansfield bars on all trailers and semi-trailers.